Practitioners are occasionally asked to induce parturition in cats.
Although this is a common technique in farm animals, it is not routinely practiced in companion animals for two main reasons:
The endocrinology of feline parturition is poorly understood. Protocols to safely induce parturition are limited.
Feline neonates are relatively immature compared to neonates of other domestic animal species; thus, premature induction of parturition might lead to elevated incidents of neonatal morbidity and mortality.
Prostaglandin F2 alpha (0.5-1.0 mg/kg SC BID for 2 injections) causes abortion or parturition if treatment given after day 25 of pregnancy. Treatment after day 55 results in clinically normal kittens that survive; lactation is normal. In one study, cloprostenol (synthetic prostaglandin F2 alpha analogue) administered to queens during 35-38 days of gestation once daily for 3 days at 5 ug/kg did not induce abortion.
Oxytocin Oxytocin (2-5 units SC or IM, or 0.5-1.25 units of a dilute solution slowly IV) can be used to propagate parturition once it has started, but it may be dangerous to use before cervical dilation is complete.
Prolactin antagonists such as bromocriptine Bromocriptine or cabergoline Cabergoline may be used, alone or in combination with prostaglandin F2 alpha, if administered daily.
The progesterone receptor blocker, aglepristone Aglepristone (RU534) has been shown to induce luteolysis in the cat and parturition in dogs (especially when associated with oxytocin). There are no published reports investigating the effect of aglepristone on induction of parturition in cats.
García Mitacek M C, Stornelli M C, Praderio R et al (2012) Efficacy of cloprostenol or aglepristone at 21-22 and 35-38 days of gestation for pregnancy termination in queens.Reprod Domest Anim 47 (Suppl 6), 200-203 PubMed.
Other sources of information
Christiansen I J (1984) Reproduction in the Dog and Cat. London: Bailliere Tindall, p 269. ISBN 0 7020 0918 0.