A biphasic basal body temperature record during pregnancy
Urman, B.C.; McComb, P.F.
Acta Europaea Fertilitatis 20(6): 371-372
1989
ISSN/ISBN: 0587-2421 PMID: 2488983 Document Number: 374434
Presented is the case of a 35-year-old woman with a biphasic basal body temperature record during an ectopic pregnancy. The patient's last menstrual period had occurred 29 days before she was admitted to the hospital with pelvic pain and vaginal spotting. The menses before this was 25 days earlier. A biphasic basal body temperature record was kept during the last menstrual cycle. Vaginal bleeding, which lasted 2 days, commenced at midcycle. 12 days after the temperature rise, the episode of vaginal bleeding that caused the patient to present at the hospital occurred. The human chorionic gonadotropin (hCG) titer was 3600 U/L at admission, 4900 U/L 3 days later, and 5600 U/L after 6 days. A vaginal scan failed to reveal a intrauterine sac, but laparoscopy showed a left ampullary pregnancy 4 x 4 x 5 cm in measurement. Given both the size of the gestation and the hCG levels, it was concluded that the ectopic pregnancy was conceived in the cycle before the most recent one. The biphasic basal body temperature record suggested that the patient had ovulated after implantation. Ovulation during pregnancy is hypothesized to be the cause of superfetation found in mares. In humans, superfetation has been recorded secondary to ovulation induced by clomiphene citrate. It is possible that some cases of presumed transmigration, where the corpus luteum is found on the ovary contralateral to the ectopic, ovulations superimposed on pregnancy may be present.