[hua7450]

Summary

Fixes #10390. Stacked on #10365 and targeting fix-chip-pregnant-income-limit-dates.

Correct Rhode Island's pregnancy Medicaid/CHIP insurance split and preserve postpartum coverage based on qualifying eligibility during the completed pregnancy. Continuation survives income changes and another pregnancy, and lasts through the last day of the month in which the 12-month postpartum period (beginning on the last day of pregnancy) ends, including across leap years.

During pregnancy, an otherwise eligible citizen at 230% FPL qualifies for Medicaid with third-party insurance and standard pregnancy CHIP when uninsured. During postpartum continuation, the original standard CHIP pathway stays CHIP; the model prevents simultaneous CHIP and Medicaid enrollment and respects take-up choices.

Authority and behavior

• 210-RICR-30-00-1 §1.6(A)(2)(a)-(b), (B) supplies the ordinary 190% Medicaid standard, the insured 253% standard, and the uninsured CHIP pathway. Stored limits include the five percentage point disregard (195% and 258%). Existing employer, individual-market, Medicare, TRICARE and CHAMPVA inputs represent third-party coverage without a dependency on Medicaid enrollment; the list is the parameter gov.states.ri.eohhs.medicaid.third_party_coverage (§ 1.9(B)(1) defines third-party liability). The insured route appears in the rule only from its August 17, 2025 version; earlier years rest on the section 1115 demonstration's Budget Population 6b (pages 3 and 15) and are unverified estimates.
• R.I. Gen. Laws §42-12.3-3(g) bases full postpartum benefits on qualifying pregnancy-time eligibility, including retroactive eligibility, and continues them through the last day of the month in which the twelve-month postpartum period ends. Current income and a subsequent pregnancy do not terminate that entitlement. The statute does not say when the period begins; the code follows 42 U.S.C. 1396a(e)(16), which covers state plans and waivers, and RI-22-0024 (page 7), which start it on the last day of pregnancy. Only the 1115 approval's wording for Budget Populations 6a and 6b ("end of the 12th month following the end of the pregnancy") gives one more month when a pregnancy ends on the 1st; the state plan groups, CHIP (RI-22-0025 CS27), RIte Start and FCEP have no conflicting text. source_conflicts/candidates.yaml records this as the unreviewed candidate us-ri:medicaid-postpartum-end-month.
• RI-22-0024: the approval letter (page 2) confirms October 1, 2022 for Medicaid's extension, and section B (page 7) starts the 12-month period on the last day of pregnancy. A monthly RI parameter retains that exact effective date.
• RI-22-0025, CS27 preserves separate CHIP through the postpartum period despite changed circumstances, including becoming eligible for Medicaid. An independent CHIP continuation flag preserves CHIP enrollment and prevents duplicate Medicaid enrollment. Medicaid remains available when eligible applicants take it up and decline CHIP.
• RI-22-0026, approval letter provides FCEP postpartum benefits through a Title XXI health services initiative (HSI). The fiscal correction gives Rhode Island's postpartum continuation no Title XIX match unless the pregnancy was covered by Medicaid and the enrollee meets Medicaid immigration requirements. RIte Start serves any person "who lacks health insurance coverage for maternity care and who is not eligible for medical assistance under Title XIX ... and Title XXI ... of the Social Security Act" (§ 42-12.3-3(b)), and CHIP and FCEP pregnancies are Title XXI coverage. It does not calculate HSI funding or assert that all federal participation is zero. Limitation: the zero match overrides any federally matched group the person also meets, such as a new pregnancy at or below 195% FPL, SSI or the adult expansion.

Required history and calendar inputs

Two new annual person inputs record facts the old day-count flags cannot establish:

• ri_pregnancy_coverage: qualifying pregnancy history (MEDICAID, CHIP, RITE_START, FCEP, or NONE). Eligibility may be established retroactively. The default NONE does not infer prior eligibility from current income or current take-up.
• ri_medicaid_pregnancy_end_date: the last completed pregnancy's end date. A newborn is not required; miscarriage and termination use the same calendar rule.

The shared monthly continuation calculation requires established history, a completed pregnancy and current RI residence. Its exclusive endpoint is the month after the month of (end date minus one day) plus 12 months; for example, a pregnancy ending January 1, 2023 is covered through December 2023, and one ending January 2, 2024 through January 2025. Missing history/date does not activate the continuation, but the existing day-count route (count_days_postpartum below the state's postpartum_coverage) still applies in every state, Rhode Island included. Without a pregnancy-history input (microdata has none), Rhode Island falls back to that day count, as other states do; #10241 sets it to 365 days from October 1, 2022. When history is NONE the model cannot tell "no qualifying coverage" from "unknown", so the day-count proxy can over-cover. This PR does not impute history in microdata.

The generic count_days_postpartum input and formula are unchanged. The mother/newborn fixture still derives the newborn's infinity default and verifies distinct enrollment.

Related work and remaining scope

The duplicate change to the federal postpartum day-count parameter has been removed. #10241 can continue dating that parameter for all states independently; RI's new calendar calculation does not use its 365-day proxy, while the day-count route does. General standard-CHIP postpartum work remains in #10363.

Merge order: #10241 (merged), then #10365, then this PR. #10363 also appends cases to is_chip_eligible_standard_pregnant_person.yaml, so whichever merges second renumbers.

After #10365 merges:

• (a) confirm GitHub retargeted this PR's base to main, or run gh pr edit 10391 --base main;
• (b) merge main again (do not rebase) if it has moved; is_pregnant_for_medicaid.yaml already holds main's Date 12-month Medicaid postpartum coverage from each state's approval #10241 cases, then Correct CHIP and Medicaid pregnancy income limits and effective dates #10365's cases, then this PR's Rhode Island block (Cases 34-40);
• (c) with Apply the CHIP no-other-coverage test to pregnancy pathways in every state #10371, whichever merges second resolves the CHIP formula to (... & ~has_disqualifying_coverage) | ri_chip_postpartum_eligible(first_month), dropping this PR's now-redundant Rhode Island insurance gate from CHIP (all six Rhode Island sources are on the CHIP list) and keeping the Rhode Island parameter for the Medicaid route; CHIP Case 24 persons 2-3 stay true.

The new monthly flags are evaluated at each month's start. Existing annual national eligibility variables read January's flag; this PR does not convert all Medicaid/CHIP outputs to monthly periods. Tests exercise the actual September/October 2022 boundary directly through the monthly calculation. Full Title XIX/Title XXI/HSI funding allocation after a later immigration-status change remains outside this eligibility correction.

Validation

Law-derived YAML cases cover income increases and decreases, false/missing history, all prior-program choices, another pregnancy, citizens and undocumented residents, month-end expiry, leap years, October 2022, state controls, CHIP retention, enrollment separation, take-up choices, and the identified Medicaid matching exclusion. Existing pregnancy, CHIP/FCEP, immigration, enrollment and FMAP cases are checked as well.

The initial legal counterexamples failed on the previous draft. The new tests were written independently from the legal sources before implementing the continuation calculation.

At f0f8add67d, before the review fixes, 142 policy YAML cases and 4 input-definition checks passed locally across the focused pregnancy, Medicaid, CHIP/FCEP, immigration, enrollment and federal-share suites.

A local review on 2026-10-26 found two critical issues (coverage one month too long for pregnancies ending on the 1st; Rhode Island dropping the day-count postpartum route), two should-address items and three suggestions. Commit adcd687fdc fixes all of them, changes the expectations of four existing cases and adds one federal-share case; those cases were checked by hand and not run locally, and CI validates them. 5ed53099cc merges #10365's updated branch, which includes main. 4cab49cd24 keeps is_medicaid_eligible.yaml Case 17 stable under either day count (person 3 is now 400 days postpartum), gives CHIP-history and Medicaid-history-without-status continuations no Title XIX match with one new federal-share case, and narrows the source-conflict candidate; these were checked by hand and not run locally. 1c78751418 merges #10365's head ae4dc7a828, which includes main with #10241, and renumbers this PR's is_pregnant_for_medicaid.yaml cases from 17-23 to 34-40. No Rhode Island expectation changes: the day count is 60 days until October 1, 2022 and 365 days after, which the cases already assumed; this was checked by hand and not run locally. ruff format and check pass. No partner contract test files are edited.

axiom: TheAxiomFoundation/rulespec-us#1935 queued