 As with other members of its family , the sicklefin lemon shark is viviparous ; the developing embryos are sustained by a placental connection formed from their depleted yolk sacs . Females give birth to one to 13 ( usually six to 12 ) pups every other year in shallow nursery areas , following a gestation period of 10 – 11 months . Unlike in the American lemon shark , cant evidence indicates this species is philopatric ( returns to the site of their birth to reproduce ) . Parturition occurs in October or November at Madagascar and Aldabra , and in January at French Polynesia ; ovulation and mating for nonpregnant females takes place at around the same time . The embryos develop a placenta after around four months of gestation , when they still possess vestiges of external gills . The young are born at a length of 45 – 80 cm ( 18 – 31 in ) . Juvenile sharks grow slowly , at a rate of 12 @.@ 5 – 15 @.@ 5 cm ( 4 @.@ 9 – 6 @.@ 1 in ) per year . Both sexes attain sexual maturity at a length of 2 @.@ 2 – 2 @.@ 4 m ( 7 @.@ 2 – 7 @.@ 9 ft ) . 
