What developmental milestone is typically reached around week 26, where the fetus can open its eyes?

Miscarriage (also called spontaneous abortion) is the loss of a pregnancy before 20 weeks of gestation, with most cases occurring in the first trimester (before 13 weeks). The most common cause is chromosomal abnormalities, followed by maternal conditions like thyroid disorders, infections, or uterine anomalies. Clinical signs include vaginal bleeding, abdominal cramping, and loss of pregnancy symptoms such as nausea and breast tenderness. Diagnosis is supported by ultrasound and quantitative hCG levels, which should double every 48–72 hours in a viable early pregnancy. A fetal heart rate is considered normal between 110–160 beats per minute.

Rationale for correct answers

A. Vaginal bleeding in the first trimester, especially when persistent or heavy, is a common sign of threatened or inevitable miscarriage. It may be accompanied by passage of clots or tissue.

B. Severe abdominal cramping or back pain is a hallmark of miscarriage due to uterine contractions and cervical dilation. It often intensifies as the pregnancy tissue is expelled.

D. Loss of pregnancy symptoms, such as resolution of nausea or breast soreness before the end of the first trimester, may indicate hormonal decline following embryonic demise.

Rationale for incorrect answers

C. Increased fundal height is not a sign of miscarriage. In fact, a decreasing or non-rising fundal height may be more indicative of pregnancy loss or intrauterine growth restriction.

E. A fetal heart rate of 140 beats per minute is within the normal range (110–160 bpm) and strongly indicates a viable pregnancy. Its presence rules out miscarriage at that moment.

Take home points

• First trimester miscarriage presents with bleeding, cramping, and loss of pregnancy symptoms.

• Chromosomal abnormalities are the most common cause.

• Normal fetal heart rate (110–160 bpm) rules out miscarriage.

• Miscarriage is confirmed by ultrasound and declining hCG levels.

Teratogen exposure during the first trimester poses the highest risk for congenital anomalies due to organogenesis, which occurs between weeks 3 and 8 of gestation. Teratogens disrupt cellular differentiation, DNA synthesis, and tissue morphogenesis, resulting in structural or functional fetal defects. Common teratogens include retinoic acid, ACE inhibitors, valproic acid, alcohol, tobacco, radiation, and certain infections such as rubella and toxoplasmosis. Severity depends on dose, timing, and genetic susceptibility. Avoidance and early counseling are crucial. No safe threshold exists for many teratogens, and even brief exposure can lead to anomalies during this critical developmental period.

Rationale for correct answers

C. Educating on teratogen avoidance is the most critical nursing intervention in the first trimester. This is the peak window for organ development, so exposure to substances like alcohol, tobacco, certain medications, or infections can lead to major congenital anomalies. Timely education minimizes preventable teratogenic risk.

Rationale for incorrect answers

A. Administering corticosteroids is used in the second or third trimester, typically between 24 and 34 weeks, to promote fetal lung maturity in cases of preterm labor risk. It does not prevent congenital anomalies and is not a first trimester intervention.

B. Monitoring fundal height is not applicable in the first trimester because the uterus remains a pelvic organ until around 12 weeks. Fundal height measurements begin after 20 weeks gestation as a tool for tracking fetal growth, not anomaly prevention.

D. Performing Leopold’s maneuvers is relevant in the third trimester, typically after 28 weeks, to assess fetal position and presentation. It is unrelated to early congenital anomaly prevention and not useful in the first trimester.

Take home points

• Teratogen exposure in the first trimester can cause irreversible structural defects.

• Weeks 3–8 are the most critical for organogenesis and highest teratogenic risk.

• Nursing education on substance avoidance is essential during early prenatal visits.

• Not all common interventions are appropriate or effective in the first trimester.