We analysed the records for 464 consecutive patients with histological
ly documented ectopic pregnancy during a 9-year period in Hong Kong an
d found a seasonal pattern. There was a statistically significant incr
ease in the likelihood of conceptions during the summer months (June-S
eptember) resulting in ectopic pregnancies as compared with the winter
months (October-February) (p less than or equal to 0.02). No such dif
ference was observed when conception occurred in other seasons.