Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
PREGNYL vs CHORIONIC GONADOTROPIN
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Human chorionic gonadotropin (h CG) acts as a luteinizing hormone (LH) agonist, binding to LH receptors in the gonads, stimulating testosterone production in males and ovulation in females.
Chorionic gonadotropin (h CG) binds to the luteinizing hormone/choriogonadotropin receptor (LHCGR) on the surface of gonadal cells, stimulating steroidogenesis and gametogenesis. In females, it triggers ovulation and luteinization; in males, it stimulates Leydig cells to produce testosterone.
FDA: Treatment of prepubertal cryptorchidism,FDA: Induction of ovulation and pregnancy in anovulatory infertile women,Off-label: Hypogonadotropic hypogonadism in males,Off-label: Assisted reproductive technology (ART) protocols
FDA-approved: Induction of ovulation in infertile females (as part of controlled ovarian hyperstimulation),FDA-approved: Treatment of prepubertal cryptorchidism,FDA-approved: Treatment of hypogonadotropic hypogonadism in males,Off-label: Weight loss (not recommended),Off-label: In vitro fertilization protocols
Intramuscular injection: 5,000-10,000 IU once weekly for 4-9 weeks for ovulation induction; 1,000-2,000 IU three times weekly for spermatogenesis.
For hypogonadotropic hypogonadism: 1000-2000 IU subcutaneously or intramuscularly 2-3 times per week. For ovulation induction: 5000-10,000 IU intramuscularly as a single dose.
Terminal elimination half-life: 23–24 hours; clinically, supports daily or every-other-day dosing; peak effect may lag due to prolonged absorption
Biphasic: initial half-life ~11 hours, terminal half-life ~23–30 hours. Single-dose half-life ~32 hours; repeated dosing may extend due to accumulation.
Primarily renal metabolism and excretion; limited hepatic metabolism.
Primarily metabolized in the liver via proteolytic degradation; undergoes renal excretion with a half-life of 24-36 hours.
Renal: 10-20% as unchanged drug; hepatic metabolism to inactive metabolites; fecal excretion negligible (<5%)
Primarily renal; intact h CG is excreted in urine. Negligible biliary/fecal elimination.
~80% bound primarily to albumin; minor binding to sex hormone-binding globulin (SHBG)
Approximately 80% bound; binds to albumin and sex hormone-binding globulin (SHBG) with low affinity.
0.5–0.7 L/kg; moderately distributed into extracellular fluid; penetrates gonadal tissues
0.3–0.5 L/kg; distributes into extracellular fluid, gonadal tissues, and poorly into fat.
Intramuscular: ~100%; Subcutaneous: comparable (~95-100%); Oral: <5% (not used)
IM/SC: ~40% to 100% (mean ~78%) due to variable absorption; IV: 100% (not typical). Oral: negligible (<1% due to degradation).
No specific guidelines; use with caution in severe renal impairment (Cr Cl <30 m L/min) due to limited data.
No specific dose adjustment guidelines available; use with caution in severe renal impairment (GFR <30 m L/min/1.73 m²).
No specific guidelines for Child-Pugh; use with caution in severe hepatic impairment.
No specific dose adjustment guidelines available; use with caution in severe hepatic impairment (Child-Pugh class C).
Not indicated for prepubertal children; for delayed puberty in males: 1,000-2,000 IU intramuscularly 2-3 times weekly for 3-6 months.
Cryptorchidism: 500-1000 IU subcutaneously or intramuscularly 2-3 times per week for 6 weeks. Delayed puberty: 500-1500 IU subcutaneously or intramuscularly 2-3 times per week.
No specific recommendations; use lowest effective dose due to potential increased sensitivity and comorbidities.
No specific dose adjustments; monitor for fluid retention and cardiovascular effects.
No FDA black box warning.
None. However, use in females requires careful monitoring to avoid ovarian hyperstimulation syndrome (OHSS), which can be severe.
Ovarian hyperstimulation syndrome (OHSS) in women,Arterial thromboembolism,Precocious puberty in males,Fluid retention,Ovarian enlargement or cyst rupture
Ovarian hyperstimulation syndrome (OHSS): Risk of severe OHSS with ascites, pleural effusion, and thromboembolic events,Multiple pregnancy: Increased risk due to ovulation induction,Thromboembolic events: Increased risk, especially in patients with prior history,Ovarian enlargement: Monitor with ultrasound,Hormonal-dependent malignancies: Caution in patients with prior history
Hypersensitivity to h CG or any component,Premature epiphyseal closure in males,Androgen-dependent neoplasia (e.g., prostate cancer),Undiagnosed uterine bleeding,Ovarian cyst or enlargement due to polycystic ovarian syndrome (PCOS),Active thromboembolic disorders
Pregnancy,Primary ovarian failure,Uncontrolled thyroid or adrenal dysfunction,Active thromboembolic disorder,Hormone-sensitive tumors (e.g., prostate, breast, ovarian),Hypersensitivity to h CG or any component
No known clinically significant food interactions. Maintain usual diet unless advised otherwise by physician.
No known food interactions.
Pregny (h CG) is not indicated for use during pregnancy. h CG is used to induce ovulation and is not continued after conception. In animal studies, high doses have shown fetal abnormalities, but human data are insufficient. First trimester: No direct fetal risk from therapeutic use as it is discontinued before implantation. Second/Third trimester: Not used. Overall, classified as FDA Pregnancy Category X for ovulation induction (contraindicated in pregnancy) but no teratogenic risk if discontinued before conception.
Chorionic gonadotropin is a pregnancy hormone; exogenous use during first trimester may theoretically alter placental hormone balance, but no increased risk of congenital anomalies has been established. However, use during pregnancy is contraindicated except as part of assisted reproductive technology protocols where its role is physiological. No fetal risks documented from therapeutic use in second or third trimester.
Human chorionic gonadotropin (h CG) is normally present in breast milk in low concentrations. Exogenous h CG is likely excreted into breast milk, but the M/P ratio is not established. Due to lack of data and potential for adverse effects in the infant (e.g., hormonal disruption), breastfeeding is not recommended during therapy. The manufacturer advises discontinuing breastfeeding or avoiding the drug.
Chorionic gonadotropin is not orally bioavailable and is likely degraded in infant gastrointestinal tract. Excretion into breast milk is unknown; M/P ratio not established. However, due to its protein nature, transfer is expected to be minimal. Use during breastfeeding is not recommended unless clearly necessary; theoretical risk of hormonal effects on infant.
Pregny is contraindicated in pregnancy. No dose adjustment is applicable as it is discontinued prior to conception. There are no pharmacokinetic data for pregnancy, but the drug is not used during gestation.
No pharmacokinetic dose adjustments are recommended in pregnancy as the drug is typically administered only prior to conception or in early pregnancy for luteal phase support. The endogenous hormone levels in pregnancy far exceed exogenous doses. No dose modification required in later trimesters because use is contraindicated.
Pregnyl (h CG) is used to trigger final follicular maturation and ovulation in assisted reproduction. Monitor for ovarian hyperstimulation syndrome (OHSS); consider withholding h CG if estradiol >4000 pg/m L or >20 follicles per ovary. Administer exactly 36 hours before oocyte retrieval. Intramuscular injection into gluteal muscle; rotate sites if repeated doses.
Chorionic gonadotropin (h CG) is used to trigger ovulation in assisted reproduction and to treat hypogonadotropic hypogonadism in males. Monitor for ovarian hyperstimulation syndrome (OHSS) in women; discontinue if severe. Do not use in women with primary ovarian failure. In males, may cause gynecomastia or fluid retention.
Use Pregnyl exactly as prescribed to trigger ovulation; timing is critical for egg retrieval.,Report severe pelvic pain, bloating, nausea, or rapid weight gain (possible OHSS) immediately.,Avoid pregnancy tests during treatment as h CG may cause false positive.,May cause injection site pain or swelling; apply warm compress if needed.,Do not discontinue without consulting your fertility specialist.
Report abdominal pain, bloating, nausea, vomiting, or rapid weight gain (signs of OHSS).,In males, report breast tenderness or swelling, or fluid retention (swollen ankles/feet).,Do not use if pregnant or breastfeeding unless directed by a specialist.,For fertility: timing of intercourse or IUI is critical; follow cycle monitoring closely.,In males: take as prescribed for testicular descent or hypogonadism; may require multiple doses.
No interactions on record
No interactions on record
Common clinical questions about PREGNYL vs CHORIONIC GONADOTROPIN, answered by our medical review team.
PREGNYL is a Gonadotropin Hormone that works by Human chorionic gonadotropin (h CG) acts as a luteinizing hormone (LH) agonist, binding to LH receptors in the gonads, stimulating testosterone production in males and ovulation in females.. CHORIONIC GONADOTROPIN is a Gonadotropin Hormone that works by Chorionic gonadotropin (h CG) binds to the luteinizing hormone/choriogonadotropin receptor (LHCGR) on the surface of gonadal cells, stimulating steroidogenesis and gametogenesis. In females, it triggers ovulation and luteinization; in males, it stimulates Leydig cells to produce testosterone.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between PREGNYL and CHORIONIC GONADOTROPIN depend on the specific clinical indication. These are both Gonadotropin Hormone agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of PREGNYL is: Intramuscular injection: 5,000-10,000 IU once weekly for 4-9 weeks for ovulation induction; 1,000-2,000 IU three times weekly for spermatogenesis.. The standard adult dose of CHORIONIC GONADOTROPIN is: For hypogonadotropic hypogonadism: 1000-2000 IU subcutaneously or intramuscularly 2-3 times per week. For ovulation induction: 5000-10,000 IU intramuscularly as a single dose.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between PREGNYL and CHORIONIC GONADOTROPIN in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. PREGNYL is classified as Category C. Pregny (hCG) is not indicated for use during pregnancy. hCG is used to induce ovulation and is not continued after conception. In animal studies, high doses have shown fetal abnorm. CHORIONIC GONADOTROPIN is classified as Category C. Chorionic gonadotropin is a pregnancy hormone; exogenous use during first trimester may theoretically alter placental hormone balance, but no increased risk of congenital anomalies. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.