Navigating the world of medications during pregnancy can be a source of significant anxiety for expectant mothers. In Singapore, the use of medicines during antenatal care is governed by strict regulations and evidence-based practices to ensure the safety of both mother and baby. Understanding what medications are commonly used, why they are prescribed, and the importance of professional medical guidance is essential for a healthy pregnancy journey.
This article explores the types of medicines used in antenatal care in Singapore, from routine supplements to emergency interventions, and explains why expert supervision from clinics like WS Law Women’s Clinic & Laparoscopic Surgery Centre is indispensable.
The Philosophy of Medication Use in Pregnancy
The guiding principle of antenatal pharmacotherapy is simple but critical: medications should only be used when the benefits to the mother and baby clearly outweigh any potential risks. This risk-benefit calculation is complex and requires the expertise of a qualified obstetrician who understands both the mother’s medical history and the latest evidence regarding fetal development.
In Singapore, the Health Sciences Authority (HSA) regulates all medications and provides safety information to healthcare professionals to guide prescribing practices . This regulatory framework ensures that any medication used during pregnancy has been carefully evaluated for safety.
Categories of Medications Used in Antenatal Care
The medicines used during pregnancy in Singapore can be broadly categorised into routine supplements, medications for common pregnancy conditions, and emergency interventions for complications.
1. Routine Nutritional Supplements
The most commonly prescribed “medicines” in antenatal care are actually nutritional supplements designed to fill dietary gaps and support fetal development.
Folic Acid: This B-vitamin is arguably the most critical nutrient in early pregnancy. It is essential for preventing neural tube defects—serious abnormalities of the brain and spine like spina bifida. Health authorities recommend that all women of childbearing age take a daily supplement of 400-800 micrograms of folic acid, ideally starting before conception and continuing through the first 12 weeks of pregnancy.
Iron: During pregnancy, blood volume increases dramatically, raising iron requirements. Iron supplements help prevent iron-deficiency anaemia, which can cause severe fatigue, weakness, and complications during delivery . Most prenatal multivitamins contain well-absorbed forms like iron bisglycinate, which is gentle on the stomach and non-constipating.
Calcium and Vitamin D: Calcium is vital for building the baby’s bones and teeth, while vitamin D ensures proper calcium absorption . Vitamin D also supports immune function and normal bone development in children.
Omega-3 Fatty Acids (DHA): DHA (docosahexaenoic acid) is crucial for the baby’s brain and visual development, particularly during the third trimester when the brain undergoes rapid growth . It is a key component of brain tissue and the retina, and adequate maternal DHA intake has been linked to improved cognitive outcomes in children.
Iodine: Iodine is essential for thyroid hormone production, which is critical for the baby’s brain development . The World Health Organization identifies iodine deficiency as the leading preventable cause of childhood developmental delay.
Comprehensive Prenatal Multivitamins: Many women opt for complete prenatal multivitamin formulations that combine all these essential nutrients. Products like Thorne Basic Prenatal and Biofinest Prenatal contain a blend of folic acid, iron, calcium, zinc, iodine, and vitamins A, C, D, E, and B-complex . These formulations are designed to support both maternal health and fetal development throughout all trimesters and even during breastfeeding.
2. Medications for Managing Pregnancy Complications
Beyond routine supplements, several prescription medications are used to manage specific pregnancy complications.
Antenatal Corticosteroids (for Preterm Birth): One of the most important emergency interventions in obstetrics is the administration of antenatal corticosteroids (ACS) to women at risk of imminent preterm delivery (before 37 weeks) . In Singapore, approximately 9% of babies are born preterm, making this a significant clinical concern.
The standard regimen used in Singapore has been two doses of 12 mg dexamethasone phosphate administered via intramuscular injection at a 12-hour interval . These steroids work by crossing the placenta and accelerating maturation of the fetal lungs, significantly reducing the risk of respiratory distress syndrome (RDS) and neonatal death.
However, recent advances in understanding have led experts to recommend adopting more widely used international regimens. A 2025 consensus statement from leading Singapore hospitals (KK Women’s and Children’s Hospital, Singapore General Hospital, and National University Hospital) recommends transitioning to either:
- Two 11.4 mg maternal intramuscular injections of betamethasone (as betamethasone phosphate and betamethasone acetate), spaced by 24 hours, OR
- Four 6 mg maternal intramuscular injections of dexamethasone phosphate, spaced by 12 hours .
These regimens achieve longer fetal exposure at lower overall concentrations, potentially reducing side effects while maintaining efficacy . Notably, the current high-dose dexamethasone regimen has been associated with maternal hyperglycaemia, particularly concerning given Singapore’s high prevalence of gestational diabetes (18.9%, compared to the global average of 13.8%).
Medications for Gestational Diabetes: For women diagnosed with gestational diabetes, management typically begins with dietary modifications and exercise. If blood glucose levels remain uncontrolled, insulin or oral medications like metformin may be prescribed under strict medical supervision.
Medications for Hypertension: Chronic hypertension or pregnancy-induced hypertension may require treatment with medications considered safe in pregnancy, such as labetalol, nifedipine, or methyldopa. ACE inhibitors and ARBs, commonly used for hypertension outside pregnancy, are generally avoided as they can cause fetal renal damage.
3. Mental Health Medications
Pregnancy can be a time of emotional vulnerability, and some women require ongoing treatment for depression or anxiety.
SSRI Antidepressants (e.g., Sertraline/Zoloft): Selective serotonin reuptake inhibitors (SSRIs) like sertraline are sometimes necessary for managing maternal depression. However, the HSA has issued important safety information regarding their use. Observational studies have shown an increased risk (less than 2-fold) of postpartum haemorrhage following exposure to SSRIs, including sertraline, especially within the month prior to birth.
Crucially, women on these medications should never stop them abruptly without consulting their doctor, as uncontrolled depression poses significant risks to both mother and baby. A specialist can weigh the risks and benefits and adjust the treatment plan accordingly.
4. Abortion-Related Medications
While not typically part of planned antenatal care, it is important to acknowledge that medications used for medical abortion are regulated in Singapore.
Mifepristone (RU486): This medication blocks progesterone, which is essential for maintaining a pregnancy. It is taken orally in the presence of an MOH-accredited abortion specialist. However, it is important to note that only Misoprostol is approved by the HSA for medical abortion in Singapore.
Misoprostol (Cytotec): This medication causes uterine contractions to expel pregnancy tissue. It is used for medical abortion up to 70 days of pregnancy and can be administered under the tongue, inside the cheek, or vaginally. It is also used in hospital settings for second-trimester abortions in cases of fetal abnormality.
The Importance of Expert Medical Supervision
Given the complexity of medication use in pregnancy, the role of a specialised women’s clinic becomes paramount. A clinic like WS Law Women’s Clinic & Laparoscopic Surgery Centre, led by Dr Law Wei Seng (MBBS, MRCOG), exemplifies the standard of care required for safe medication management.
1. Personalised Risk Assessment
An expert obstetrician does not simply consult a list of “safe” and “unsafe” drugs. They conduct a comprehensive risk-benefit analysis, considering the mother’s specific medical conditions, the stage of pregnancy, and the latest clinical evidence.
2. Safe Management of Pre-Existing Conditions
For women entering pregnancy with chronic conditions requiring medication—such as hypertension, diabetes, or depression—an expert clinic can safely transition them to pregnancy-appropriate alternatives and monitor them closely.
3. Guidance on Self-Medication
Many over-the-counter medications that seem harmless can pose risks during pregnancy. A trusted clinic provides clear guidance on what is safe for common ailments like colds, headaches, and heartburn, preventing inadvertent exposure to harmful substances.
4. Reassurance in Case of Accidental Exposure
If a woman has taken a medication before realising she was pregnant, panic is common. An expert consultation provides an accurate, evidence-based assessment of the actual risk based on the specific drug, dosage, and timing of exposure, often providing crucial reassurance.
Frequently Asked Questions (FAQs)
1. Is it safe to take folic acid throughout my entire pregnancy?
Yes, folic acid is safe and beneficial throughout pregnancy. While it is most critical in the first 12 weeks for preventing neural tube defects, it continues to support red blood cell production and overall fetal development. Most prenatal multivitamins contain folic acid and are designed to be taken throughout pregnancy and even during breastfeeding.
2. What are the risks of taking antenatal steroids for preterm labour?
Antenatal corticosteroids are a life-saving intervention that significantly reduces the risk of respiratory distress and death in preterm infants . However, they are not without risks. They can cause temporary maternal hyperglycaemia, particularly concerning for women with gestational diabetes . Studies have also suggested potential long-term associations with reduced birth measurements and, in some cases, impacts on childhood academic performance, though these findings require further investigation and must be weighed against the significant benefits of survival . Your obstetrician will carefully assess whether the benefits outweigh the risks in your specific situation.
3. I take medication for depression. Do I need to stop it now that I’m pregnant?
Absolutely not. Abruptly stopping antidepressant medication can lead to a relapse of depression, which itself poses significant risks to both you and your baby. However, you should consult your obstetrician immediately. They can review your medication and, if necessary, work with your mental health provider to adjust it to the safest possible option for pregnancy. For example, if you are taking an SSRI like sertraline, your doctor will discuss the small increased risk of postpartum haemorrhage and plan for appropriate monitoring closer to your due date.
4. Do I need to take a separate DHA supplement, or is it included in prenatal vitamins?
Many comprehensive prenatal multivitamins now include DHA. However, not all do. If you do not consume fatty fish regularly (2-3 servings per week of low-mercury options like salmon or sardines), you should ask your doctor whether a separate DHA supplement is recommended. DHA is particularly important in the third trimester for your baby’s brain and visual development.
5. What should I do if I accidentally took a medication before knowing I was pregnant?
First, do not panic. Many medications have a wide safety margin, and the risk of harm from a single exposure is often low. However, you should contact your obstetrician as soon as possible. Provide them with the name of the medication, the dose, and the timing of when you took it. They can provide an accurate, evidence-based assessment of any potential risk and advise you on the next steps. Having this conversation with a professional is far better than relying on Dr. Google and will give you the reassurance you need.
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