A reproduction specialist term of art for a situation in which a fertilised egg triggers an elevation of hCG–chorionic gonadotropin, but doesn’t implant in the endometrium, passes through the cervical os and is lost.
Its name obtains from the fact that the lack of a gestational sac makes it impossible to confirm fertilisation by ultrasonography.
Aetiology, chemical pregnancy
• Uterine defect–e.g., fibroids
• Endometrial defect–e.g., luteal phase or other hormonal defect
• Fetal chromosome defect–e.g., blighted ovum
Clinical findings, chemical pregnancy
• Usually asymptomatic
• Early or late period
• Positive pregnancy test
• Vaginal bleeding
• Decreasing hCG levels
• Abdominal cramps
Synonym Very early miscarriage