Case Study: Human Placental Lactogen and Hyperprolactinemia in Pregnancy

Case Study: Human Placental Lactogen and Hyperprolactinemia in Pregnancy

Patient Profile: Mrs. A, a 32-year-old primigravida, presents to the obstetrics clinic at 20 weeks gestation for a routine prenatal check-up. She has a history of irregular menstrual cycles and difficulty conceiving, for which she underwent fertility treatment to achieve this pregnancy. Mrs. A has noticed occasional breast tenderness and nipple discharge but attributes it to hormonal changes of pregnancy. Her medical history is otherwise unremarkable, and she denies any significant past medical or surgical history.

Clinical Presentation: During the prenatal visit, Mrs. A reports intermittent episodes of breast tenderness and milky discharge from her nipples. She is concerned about these symptoms, as they started early in pregnancy and have persisted. On examination, her breasts are slightly enlarged, and bilateral nipple discharge is noted upon palpation. There are no signs of inflammation or masses. Mrs. A’s vital signs are within normal limits, and the remainder of her physical examination is unremarkable.

Investigations: Given Mrs. A’s symptoms of persistent nipple discharge and breast tenderness, further investigation is warranted to evaluate for hyperprolactinemia. A serum prolactin level is obtained, revealing elevated levels (>200 ng/mL). Additional laboratory tests, including thyroid function tests and serum human chorionic gonadotropin (hCG) levels, are within normal limits. An ultrasound examination confirms a singleton intrauterine pregnancy with appropriate fetal growth and no evidence of gestational trophoblastic disease.

Diagnosis and Management: Based on the clinical presentation and laboratory findings, Mrs. A is diagnosed with hyperprolactinemia in pregnancy. The elevated prolactin levels are attributed to the physiological changes associated with gestation, specifically the production of human placental lactogen (hPL). Mrs. A is counseled regarding the implications of hyperprolactinemia on her pregnancy, including the risk of preterm birth and preeclampsia. Given the absence of symptoms suggestive of pituitary adenoma or other underlying pathology, observation and close monitoring of prolactin levels throughout pregnancy are recommended.

Follow-Up: Mrs. A continues prenatal care with regular follow-up visits to monitor her pregnancy progress and prolactin levels. Serial ultrasounds demonstrate normal fetal growth and development, with no evidence of complications. Despite the presence of hyperprolactinemia, Mrs. A’s pregnancy remains uncomplicated, and she delivers a healthy term infant via spontaneous vaginal delivery at 39 weeks gestation. Postpartum, her prolactin levels gradually normalize, and she successfully initiates breastfeeding without difficulty.

Discussion: This case highlights the complex interplay between human placental lactogen (hPL) and hyperprolactinemia during pregnancy. Elevated prolactin levels, secondary to increased hPL production, can mimic pathological hyperprolactinemia and present diagnostic challenges for clinicians. In cases like Mrs. A’s, where there are no concerning symptoms or signs of pituitary pathology, close monitoring and reassurance are often sufficient. However, awareness of the potential implications of hyperprolactinemia on maternal and fetal health is essential for appropriate counseling and management. Further research is needed to elucidate the long-term effects of hyperprolactinemia in pregnancy and optimize clinical care for affected individuals.

Relaxin’s Potential as a Bridge over Troubled Waters of Preterm Birth