A retrospective review of 29 pregnancies in 25 bitches diagnosed with hypoluteodism and treated with low-dose medroxyprogesterone plus withdrawal 24-48 hours before cesarean found 79.3% progesterone decline in weeks 5-6 and 86.2% term maintenance, without an untreated comparison.
Key findings
- P4 declined in weeks 5-6 in 79.3%; 25/29 pregnancies (86.2%) reached term. Four failed, including three abortions and one fetal mummification. Among 110 live births, 94.5% survived to weaning. No female virilization or monitored maternal complications were reported.
Why this matters globally
The data can inform hormone-monitoring hypotheses and discourage open-ended progestin use, while emphasizing potential labor, metabolic, mammary, and long-term offspring risks.
Thai researcher contribution
The Mahanakorn University of Technology team generated canine reproductive records and a testable P4 surveillance and drug-withdrawal protocol.
Limitations to consider
This small retrospective series has 25 dogs, 29 pregnancies, breed concentration, and no untreated control. Treatment effects cannot be separated from selection or natural history, repeated pregnancies may not be independent, and absent rare events do not establish long-term safety.